Cylinder Head/Valves Service Information; Cylinder Head/Valves Specifications - Honda 1988 Z50R Service Manual

6. CYLINDER HEAD/ VALVES
SERVICE INFORMATION
TROUBLESHOOTING
CAMSHAFT/ROCKER ARM REMOVAL
CYLINDER HEAD REMOVAL
CYLINDER HEAD DISASSEMBLY
6 - 1
6 -2
6 -3
6 -6
6-6
VALVE GUIDE REPLACEMENT 6 -8
VALVE SEAT INSPECTION/REFACING 6-9
CYLINDER HEAD ASSEMBLY 6-11
CYLINDER HEAD INSTALLATION 6-12
CAMSHAFT INSTALLATION 6 -13
SERVICE INFORMATION
GENERAL
• This section covers cylinder head, valves, camshaft and rocker arm maintenance.
• Remove the front wheel (page ' 1- 4) to allow clearance for cylinder head removal.
• Camshaft lubrication oil is fed to the cylinder head through an oil control orifi ce in the crankcase. Be sure that this orifice
is not clogged and that new D-rings and dowel pins are in place before installing the cylinder head.
SPECIFICATIONS
ITEM STANDARD
Camshaft journal 0 .0 .
R
19.942 - 19.955
l
28.942 - 28.955
Cam lobe height
IN
27 .885 28.005
EX
26.016 - 26.136
After '91
IN
20.055
Cam lobe height
EX 20.063
End hole 1.0. R
20.010- 20.031
l
29.010- 29.031
Camshafl ~ to ~e nd
hole clearance R 0.0100- 0 .025
l 0 .01 0 - 0 .025
Rocker arm I.D.
10.000 10.015
Rocker arm shaft
0.0.
9.977-9.987
Cylinder head warpage
Valve spring free length
I
INNER
32 .78
I
OUTER
35.55
After
'91
Valve spring free length
33 .34
Valve stem
0.0.
Valve guide 1.0.
Stem ~ to ~ guide clearance
Valve seat width
TORQUE VALUES
Tappet hole cap
Cylinder head cover nut
Cam s procket bolt
Valve adjusting lock nut
IN
4.970- 4 .985
EX
4 .955- 4 .970
IN/ EX
5.000 5.012
IN
0.015-0.042
EX
0 .030- 0.057
IN/ EX
1.0 1.3
12
N·ml1 .2 kg -m . 9 ft -Ib)
11 N'm 11.1
kg -m , 8
ft· lb)
10
N'm(1 .0 kg -m ,
7.2
ft·lb)
9 N·mlO .9
kg -m 6 .5 ft -Ib)
(0.785 1-0.7856)
( 1.1394 - 1.1400)
(1 .0980 1.1 026)
11 .0242 - 1.0290)
(0.790)
(0.791)
(0.787 8 -0.7 886)
11 .1421 - 1.1430)
(0.0004-0.0010)
(0.0004- 0.0010)
(0.3937 0.3943)
(0.3923- 0 .3932)
-
(1.291)
( 1.400)
(1.314)
(0. 1957 0 .1963)
(0 .1951-0.1957)
(0.1969 0.1973 )
(0 .0006-0.0017 )
(0.0012 - 0 .0022 )
(0 .04
0 .05)
mm (in)
SERVICE LIMIT
19.75 (0 .778)
28.75 (1 .1321
27.55 (1.0B5)
25.69 (1.011)
19.67
(0.775)
19.66 (0 .774)
20.20
(0.795)
29.20 ( 1.150)
0
.10 (0.004 )
0 .10
(0.004 )
10.10
10.3981
9.9 1 (0.3 90)
0.05 10 .0021
31.2
( 1.23)
34.0
11.341
31 .8
( 1.25)
4 .92 (0.194 )
4.92 (0 .194)
5.03
10. 1981
0.08 (0 .003)
0.10
(0.004)
2.0 (0 .08)
6-1